a) A kind of drama having a musical accompaniment to intensify the effect of certain scenes (archaic).
b) A drama abounding in romantic sentiment and agonizing situations, with a musical accompaniment only in parts which are especially thrilling or pathetic. In opera, a passage in which the orchestra plays a somewhat descriptive accompaniment, while the actor speaks; as, the melodrama in the grave digging scene of Beethovens "Fidelio".
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